Hello, Sorry for the lack of clarity, I thought I was clear about the package : it's the function allEffects from the package effects.
Here is my example again (unfortunately I can't give the data) : The data concerns effects of 3 treatments on the tumoral volume of mice. > head(data) Id Série Traitement vTum temps Volume 55656.1 55656 7 3 1 1 14.03 55805.1 55805 7 3 3 1 59.92 55829.1 55829 7 3 1 1 15.31 55806.1 55806 7 3 2 1 28.01 50725.1 50725 7 3 2 1 34.48 55737.1 55737 7 3 2 1 43.56 vTum is a factor coding for the qualitative initial volume, from small to big, temps is the time (integer) in month since beginning of treatment, and Série is a factor coding for the batch. Data is unbalanced. I fit a linear model as follows: > lm1=lm(Volume ~ temps + Traitement:temps + Série , data) And then I try to use allEffects to compute (and then plot) the effects of the interaction: > eff.lm1 <- allEffects(mod=lm1, xlevels=list(temps=c(1:3), Traitement=1:3)) And here is the error I get: Error in apply(mod.matrix[, components], 1, prod) : index out of range In the example given in the help page there are factor variables and numeric variables so I don't think the problem comes from here. Any help is welcome here. Cheers, Jonas Joris Meys a écrit : > Please, read the posting guide: > - provide a minimal example > - tell us from which package the function is coming > > I guess you used the function allEffects() from the package effects, and did : > eff.lm1 <- allEffect(lm1) > > Then I guess that there's something wrong with the variables you put > into the model. Sure they're factor variables and not numeric? > > Cheers > Joris > > > > On Thu, Jun 17, 2010 at 6:03 PM, Jonas Mandel <jonas.man...@curie.fr> wrote: >> Dear R users, >> >> I have some trouble using the allEffects() function to compute and >> display effect plots for a linear model. >> My data is quite simple, it concerns effects of 3 treatments on the >> tumoral volume of mice. vTum codes for the qualitative initial volume, >> from small to big, temps is the time in month since beginning of >> treatment, and Série codes for the batch. Data is unbalanced. >> >>> head(data) >> Id Série Traitement vTum temps Volume >> 55656.1 55656 7 3 1 1 14.03 >> 55805.1 55805 7 3 3 1 59.92 >> 55829.1 55829 7 3 1 1 15.31 >> 55806.1 55806 7 3 2 1 28.01 >> 50725.1 50725 7 3 2 1 34.48 >> 55737.1 55737 7 3 2 1 43.56 >> >> >> The linear model is also quite simple : >>> lm1=lm(Volume ~ temps + Traitement:temps + Série , data) >> But when I try to use allEffects() I get this error: >>> eff.lm1 <- allEffect(mod=lm1, >> Error in apply(mod.matrix[, components], 1, prod) : index out of range >> >> I read the help and the example but I don't understand the reason why it >> doesn't work. Can you help me ? >> Thanks >> >> >> -- >> Jonas Mandel >> >> ______________________________________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. >> > > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.